Air valve



Jan. 14; 1947. w. G. CHRlS TIANSEN AIR VALVE Filed Oct. 14, 1943 INVENTOR- /4 6. CMQ/jT/A/MEM r #TTORNEYS Patented Jan. 14, 1947 AIR VALVE Walter G. Christiansen, Essex County, N. J.

Application October 14, 1943, Serial No. 506,166

8 Claims.

The present invention relates to air valves for intermittently heated apparatus and devices, and more particularly for the radiators in steam heating systems.

The invention is of particular utility in connection with steam radiators, and will accordingly be described in detail in connection with a steam radiator heating system.

Various types of automatic air or vent valves are at present employed on steam radiators which are constructed and designed to permit the discharge of the air in the radiator system by the incoming steam, and which, on becoming filled with steam, automatically close and thus prevent further discharge. Steam continuously condenses against the cooler walls of the valve body and collects therein.- Although provision is usually made for the drainage of the con densed water into the radiator and thence into a drain pipe, it often happens with the air valves now in use that the valve becomes sealed off from the radiator owing to the collection of a body of water in the lowerparts of the valve. In consequence, during the next heating period of the radiator, the entering steam is unable to effect discharge of the collected body of air in the radiator, with the result that the radiator ceases to function either wholly or partially. Because of the low pressure usually prevailing in steam heating systems, a relatively small head of water in the air valve is sufficient to seal it effectively. When this happens, one has to break this water seal by jarring the valve, or by taking it off and shaking out the water. This is more than the average householder can be counted on to do, and as a result, the failure of the air valve causes frequent annoyance. This is particularly so because the failure of the valves usually occurs when their proper operation is most needed, namely, in the colder periods of a winter season when the heating cycles are longest and the amount of steam entering the valve and condensing therein is greatest. It will be evident that even only partial sealing of the valve by collected condensate will slow down or impede the discharge of air out of the radiator, and consequently reduce the rate at which heat can be supplied to the room.

Attempts have been made to prevent the collection of water in the air valve by providing two separate paths, one for air (and steam) and the other serving as a condensate return path,

but the constructions heretofore devised have H proved to be unsatisfactory for one reason or another. In one type of such double path valve, V

two separate connections from the valve body to the radiator are provided, one for air (and subsequently steam), and the other for the condensate, the first being arranged above the second. This type of construction is objectionable because two separate holes have to be drilled into the radiator, which have to be properly sealed, and, additionally, because special connections have to be provided between the separate conduits and the radiator, it being, of course, impossible to provide a simple threaded connection for both conduits.

Usually this type of valve requires two unions for connecting the two conduits or pipes to the radiator; also, the lining up must be accurate and the tightening of the connections to the radiator must be carefully and skillfully done to prevent strains from arising in the system. The removal of the valve for examination or repair is complicated by the fact that two connections must be synchronously undone, an operation which may be very difficult if rusting or sticking in the threads has occurred; and on re-mounting the valve, the previously mentioned difiiculties of assembly are again encountered.

In another type of structure, a single connection between the valve and radiator is presout, but it is partitioned so as to provide two separate paths. In. this construction, if the usual size of piping is employed, a path of very limited cross-section is provided both for the air and the condensate, with the result that clogging is very liable to occur, while only small collections of water in the air path are sumcient to interfere with the further flow of air therethrough, it being recognized that with the reduction in the cross-section of the passageway, the high surface tension of water becomes a factor in promoting the development of a plug of water in the air passageway, this phenomenon especially favoring the retention of drops of the radiator, whereby the effective opening is reduced. In consequence, the whole purpose of the arrangement is defeated.

It is the general object of the invention to.

provide an air valve for radiators and the like which isproof against water-logging, is of simple and compact construction, is capable of being mounted on the radiator by 'a simple screw threaded connection, and is thoroughly reliable in operation. Other objects of the invention will appear as the more detailed description thereof proceeds.

The air valve of the presentjinvention also em available.

arranged and so related to a common connection to the radiator that the advantages of prior devices are secured and even increased while their disadvantages are eliminated. In my improved construction, only a single connection between the valve and radiator is employed so that a single-hole mounting, with its obvious advantages, can be utilized. Furthermore, the connection or pipe entering the hole in the radiator is common to the air and condensate paths, so that both air and water have a maximum of flow cross-section The separate paths for the air and water begin at a point beyond the radiator hole and each of these paths may be as large as, or even larger than, that afforded by the pipe section which connects the valve with the radiator. The air pipe leads from such pipe section in an upward vertical direction until it debouches into the body of the valve, more or less at the center thereof. The condensate return pipe leads from the bottom of the valve body to a point of connection with the air pipe and, as already indicated, such point is located at 'a distance from the radiator mounting.

Th present invention presents further improvements in various details of structure whereby the development of a water seal at various points is effectively prevented, all of which will be described in detail by reference to the accompanying drawing which shows two satisfactory embodiments of the invention. In said drawing,

Fig. 1 is a vertical sectional view of a valve constructed in accordance with the invention;

Fig. 2 is an end view inelevation; While Fig. 3 is a section along the plane 33 of Fig. 1; while Fig. 4 is a vertical sectional view of a modification with parts omitted.

Referring to the drawing, the valve is shown as composed of a body ii! having a removable cap l which is provided with a valve seat l2 containing a discharge opening 53. The latter is controlled by a needle valve M which is actuated by any suitable type of thermostatic member, there being shown by way of illustration an expansibl drum or diaphragm !5 supported upon spaced lugs or bosses l6. It will be understood that while the valve is cold, the diaphragm I5 is contracted and the needle valve 14 is in retracted condition. Upon the admission of steam to the radiator, shown iragmentarily at IT, steam ultimately enters the valve body I0 and heats the diaphragm IS. The latter then expands and ultimately the valve it closes the discharge opening l3.

It will be understood that the specific internal construction of the discharge port l3 and the valve head [4 controlling the same, and likewise the thermostatic element associated with the valve head, forms no part of the present invention, and that any suitable thermostatically operated valve can be associated with the structural features constituting my invention and which I shall now describe.

The air valve assembly is mounted by way of a short threaded pipe section or connection it in a tapped hole It in the side wall of the radiator II. The pipe section l8 may be so dimensioned that it will fit into the standard threaded opening in radiators. The pipe connection 18 leads upwardly to a point 20 ,from which there leads an air and steam conduit 2| and a condensate return conduit 23. The upper portion of the conduit 2| is downwardly inclined, as shown at 22, as it enters the body of the valve; While the conduit 23 leads from the bottom of the valve body IE3. As can be seen from Fig. 1, the flow cross-section available to the incoming air, air and steam, or steam, and to the discharging condensate, is in each case quite large and is in fact at least as large at any point as the internal cross-section of the pipe section I8. It will be noted that where a separation of the paths for the air and for the condensate occurs, this separation is effected at a point at which the flow cross-section available to each fluid need not be sacrificed for the other, the pipe section It! being free and unobstructed .by any partition or otherwise, and being available both to the air and to the water.

It will also be observed that by virtue of the downward inclination of the upper portion 22 of conduit 2!, the collection of condensate in such upper portion is prevented, since such condensate will readily flow into the body of the valve and thence into the condensate return pipe 23.

To insure further against the collection of condensate in the portion 22, and to prevent any condensate collecting on the upper inside walls of the valve body from entering the conduit 2|, I cause the discharge end 22 of such pipe to extend beyond the wall of the body Iii. This construction discourages the formation of a mound of condensate at the mouth of the conduit section 22. The full cross-section of the outlet of the pipe portion 22 is thus made available for the iiow of air and steam.

The condensate return conduit 23 may have a continuously downward slope from the bottom of the valve body it) to the point of juncture 20 with the pipe section l3. I prefer, however, to provide the conduit 23 with a depressed portion 23' which forms a water trap or seal which insures that the air and steam will flow through the conduit 2! rather than the conduit 23. In this way the gas and liquid circuits are kept separate except for the common pipe section H3. The discharge end of the conduit 23, indicated at 24, is preferably disposed a considerable distance above the outlet of the pipe section it, whereby a sufiicient head is provided for the water discharging into the junction 20 to insure its rapid downward flow through the pipe l8. By reason of such structure, the discharging condensate will flow with sufiicient speed to secure complete drainage. The collection of water within the pipe I8 is further prevented by giving the discharge portion of such pipe a slight downward inclination by suitably shaping the interior walls thereof. This can be done either by boring the discharge end portion at a downward angle to the horizontal, or by bevelling or tapering the bottom wall portion, as indicated at 25 in Fig. 4. The tendency of water to collect at a discharge edge by reason of its high surface tension, is further discouraged in accordance with the invention by extending the bottom portion of the pipe section l8 beyond the upper portion, as indicated at 26 (Fig. 4). The bottom wall is preferablyextended to more or less of a point, and if desired, the forward edge may be serrated as indicated at 21, to insure dropping off of the condensate.

to form a seal or a partial seal in the air or airsteam circuit. The arrangement and construction are such that in the common pipe section [8 there can occur no accumulation of water, and the continuous discharge of condensate through such pipe section occurs only in the form of a thin film so that when the supply of steam is terminated at the end of the period of heating of the radiator or other vessel or chamber to which the valve is applied, only a very small amount of water is contained in the pipe section IB, in fact only about enough to wet the bottom wall portion thereof. Upon the initiation of the next heating period, therefore, there is no obstruction or resistance to the flow of the displaced air into and through the conduit 2|.

It will be evident further that my improved valve can be utilized on existing radiators by simply constructing the pipe section [8 of standard size with standard thread. The valve can be attached to, for example, a radiator, as a com"- pletely assembled unit; and despite the fact that only a single connection with the radiator is provided, flow areas quite as large as in the case of a two point connection, are provided for the air and water.

It will be observed that the bottom portion it of the valve body and the arrangement and configuration of the conduits I8, 2|, 22 and 23 are of such simple construction and outline that these parts can be cast integrally as a single piece, no machining being necessary except for the threading l9 and perhaps for the upper part of the body ID to insure a tight fit with the cap ll. Also, no

additional internal parts are required except for the bellows l5 and valve head [4, so that an extremely simple and inexpensive structure is provided by the present invention.

I claim:

1. A valve for automatically controlling the discharge of a relatively cold body of air from a chamber into which a hot vapor or gas is being introduced, comprising, in combination with the body of the valve, a discharge port therein and a thermostatically actuated valve head controlling said port, an air and vapor conduit debouching into the valve body and through the wall of the valve body at a point spaced above the bottom thereof, a condensate return conduit connected with the body at the bottom thereof and of sufliciently large cross-section to drain condensed vapor as rapidly as it is formed, and a connecting conduit adapted to be mounted upon a wall of the chamber and to lead into the interior of the chamber, said two first-mentioned conduits joining the connecting conduit exteriorly of the valve body at a point removed from the region of mounting of the latter, the whole of the interior of said connecting conduit being in communication with each of the two first-mentioned conduits.

2. An air-valve for steam radiators comprising a valve body, a vent for said body, a thermostatically actuated valve in said body for controlling said vent, an air and steam conduit debouching into the valve body and through the wall of the valve body at a point spaced above the bottom thereof, a condensate return conduit connected with the body at the bottom thereof and of sufiiciently large cross-section to drain condensed vapor as rapidly as it is formed, and a pipe section adapted to be fitted within an aperture in the radiator wall and connected with the said two conduits exteriorly of the valve body in a region removed from the portion of the pipe section entering said aperture, the whole interior of said pipe section communicating with each of said conduits.

3. An air valve as defined in claim 2 wherein the air and steam conduit rises from the point of juncture with the pipe section to a point above the region of its debouchment into the valve body, and is downwardly inclined from such last-mentioned point to said region.

a. An air valve as defined in claim 2 wherein the air and steam conduit rises from the point of juncture with the pipe section to a point above the region of its debouchment into the valve body, and is downwardly inclined from such last-mentioned point to said region, said conduit having a discharge end protruding inwardly beyond the wall of the valve body, whereby collection of condensate at the edge of the discharge end is discouraged.

5. An air valve as defined in claim 2 wherein the condensate conduit is provided with a water trap whereby such conduit becomes closed to air and steam, and such gaseous material is compelled to flow only through the air conduit.

6. An air valve as defined in claim 2 wherein the condensate conduit is provided with a depressed portion forming a water seal and is disposed above the pipe section, whereby a head is provided to insure rapid flow of condensate from said seal to and through said pipe section.

7. An air-valve for steam radiators comprising a valve body, a vent forsaid body, a thermostatically actuated valve in said body for controlling said vent, an air and steam conduit debouching into the valve body above the bottom thereof, a condensate return conduit connected with the body at the bottom thereof and of sufiiciently large cross-section to drain condensed vapor as rapidly as it is formed, and a pipe section adapted to be fitted within an aperture in the radiator wall and connected with the said two conduits in a region removed from the portion thereof entering said aperture, the Whole interior of said pipe section communicating with each of said conduits, and the bottom wall portion of the discharge end of the pipe section being extended beyond the edge of the upper wall portion thereof and being serrated to promote the discharge of condensate.

8. An air valve for steam radiators comprising a unitary casting providing a portion of the valve body and a roughly Y-shaped pipe structure including a condensate return conduit leading from the bottom of the valve body portion, an air and steam conduit rising from the point of juncture with the condensate return conduit and externally of the valve body and debouching into the valve body above the bottom thereof, the third branch of the Y-structure comprising a pipe section leading downwardy from the point of juncture of the said two conduits and adapted to provide the communication with the radiator wall, the whole interior of said pipe section connecting with each of said conduits, an upper body section fitted to the said valve body portion, a vent in said upper section, and a thermostatically operated valve member inside the valve body and controlling said vent.

WALTER G. CHRISTIANSEN. 

